In most of the books I have read, when you have a dragon shifter, they were usually born as dragons from an egg (correct me if I'm wrong, I haven't read an enormous amount). However, I want my dragon shifters to have been born human - and not even know they're shifters until after their 25th birthday, which in my race is when they come of age.

The only way they can sometimes be recognised before their change is by another Dragon shifter, but there are only two others left in my book.

The only thing that's bothering me is this: if they're born human and they change into a dragon, is having them hunt, then kill and eat other humans or animals in dragon form extremely creepy (not that it wouldn't be anyway ) but at their core they are human, so I'm not quite sure how to handle it. Thoughts?

I think I would depend on whether or not humans are the primary food source of dragons (like it's expected), or if just some dragons are nasty and choose to eat humans. There's a big difference.

I haven't read anything in which any characters or races are identified as "dragon shifters" (and my browser is telling me that "shifter" is a misspelled word), but of the two works that your question made me think of, neither had the dragon-descendants hatching. The first is the Dungeons & Dragons role-playing games (or perhaps just the derived-but-much-modified Pathfinder), which apparently in editions that have come out since I've paid much attention to details have "dragonborn" races, which seem to be just ordinary humans with a few additional powers. The other was one of the stories in Kai Lung's Golden Hours, which "reveals" (one is never sure which details of Kai Lung's stories he believes, and thus the reader is supposed to think are part of the background of Bramah's faux-mythic-China, and which are purely inventions to make the story work) that dragons are powerful beings that can change into literally any shape, and have children in any such shape, with the sole exception that in every shape a dragon has a tail .

Not seeing it as creepy as much as a great opportunity for mental anguish, comparison and contrast with others, and how the character comes to terms with what they are.

How do normal people view dragons? The character likely starts out like that. Fear and loathing? Abject adoration? "A dragowhat?"

How would you feel if you had to do something you used to abhor? Is it still wrong? Do you pick and choose and mentally tell yourself it's for the greater good? or do you just shrug and say "I yam what I yam."

Dealing with that seems a powerful motivator.